A recent prospective cohort study examined the long-term health outcomes associated with weight regain after substantial weight loss following bariatric surgery.
"Partial weight regain after substantial weight loss was associated with a less favorable cardiovascular risk profile and an increased incidence of both microvascular and macrovascular diseases; however, no association with life expectancy was observed," reported Lena M.S. Carlsson from the Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Sweden, and colleagues.
Published in The Lancet Regional Health - Europe, Carlsson and colleagues analyzed data from 1,346 participants from the Swedish Obese Subjects (SOS) study who underwent bariatric surgery between 1987 and 2001. They compared individuals who regained at least 20% of their initial weight loss by year 4 with those who regained less than 20%. The median follow-up was 27 years.
Findings showed that microvascular disease was more common in the regain group (11 vs. 8.7 per 1,000 person-years). Major cardiovascular events, including heart attacks and strokes, were also slightly higher (15.7 vs. 13 per 1,000 person-years). However, overall mortality rates remained nearly identical (12.4 per 1,000 person-years). Cancer incidence showed no significant difference.
Participants were aged 37 to 60 at the time of surgery and had a BMI of at least 34 kg/m² for men and 38 kg/m² for women. Bariatric procedures included gastric banding, vertical banded gastroplasty, and gastric bypass. Statistical analyses confirmed the findings even with a stricter 30% weight regain threshold.
Despite no mortality difference, the study highlights the need for long-term monitoring and interventions to reduce cardiovascular risk in patients who regain weight post-surgery, noted researchers. Weight regains were not a predefined analysis in the original SOS study, making these findings exploratory. They also noted that the study’s predominantly Scandinavian population may limit generalizability.
Future research should explore additional long-term consequences of weight regain and strategies for maintaining weight loss.
These findings contribute to ongoing discussions about bariatric surgery’s long-term impact and the importance of sustained patient monitoring.
Conflicts of interest are available in the published study.